Water dimer diffusion on Pd{111} assisted by an H-bond donor-acceptor tunneling exchange

Based on the results of density functional theory calculations, a novel mechanism for the diffusion of water dimers on metal surfaces is proposed, which relies on the ability of H bonds to rearrange through quantum tunneling. The mechanism involves quasifree rotation of the dimer and exchange of H-bond donor and acceptor molecules. At appropriate temperatures, water dimers diffuse more rapidly than water monomers, thus providing a physical explanation for the experimentally measured high diffusivity of water dimers on Pd{111} [Mitsui et al., Science 297, 1850 (2002)]

Cross-sectional study of the burden of vector-borne and soil-transmitted polyparasitism in rural communities of Coast Province, Kenya.

BACKGROUND: In coastal Kenya, infection of human populations by a variety of parasites often results in co-infection or poly-parasitism. These parasitic infections, separately and in conjunction, are a major cause of chronic clinical and sub-clinical human disease and exert a long-term toll on economic welfare of affected populations. Risk factors for these infections are often shared and overlap in space, resulting in interrelated patterns of transmission that need to be considered at different spatial scales. Integration of novel quantitative tools and qualitative approaches is needed to analyze transmission dynamics and design effective interventions. METHODOLOGY: Our study was focused on detecting spatial and demographic patterns of single- and co-infection in six villages in coastal Kenya. Individual and household level data were acquired using cross-sectional, socio-economic, and entomological surveys. Generalized additive models (GAMs and GAMMs) were applied to determine risk factors for infection and co-infections. Spatial analysis techniques were used to detect local clusters of single and multiple infections. PRINCIPAL FINDINGS: Of the 5,713 tested individuals, more than 50% were infected with at least one parasite and nearly 20% showed co-infections. Infections with Schistosoma haematobium (26.0%) and hookworm (21.4%) were most common, as was co-infection by both (6.3%). Single and co-infections shared similar environmental and socio-demographic risk factors. The prevalence of single and multiple infections was heterogeneous among and within communities. Clusters of single and co-infections were detected in each village, often spatially overlapped, and were associated with lower SES and household crowding. CONCLUSION: Parasitic infections and co-infections are widespread in coastal Kenya, and their distributions are heterogeneous across landscapes, but inter-related. We highlighted how shared risk factors are associated with high prevalence of single infections and can result in spatial clustering of co-infections. Spatial heterogeneity and synergistic risk factors for polyparasitism need to be considered when designing surveillance and intervention strategies

Measuring fitness of Kenyan children with polyparasitic infections using the 20-meter shuttle run test as a morbidity metric.

BACKGROUND: To date, there has been no standardized approach to the assessment of aerobic fitness among children who harbor parasites. In quantifying the disability associated with individual or multiple chronic infections, accurate measures of physical fitness are important metrics. This is because exercise intolerance, as seen with anemia and many other chronic disorders, reflects the body's inability to maintain adequate oxygen supply (VO(2) max) to the motor tissues, which is frequently linked to reduced quality-of-life in terms of physical and job performance. The objective of our study was to examine the associations between polyparasitism, anemia, and reduced fitness in a high risk Kenyan population using novel implementation of the 20-meter shuttle run test (20mSRT), a well-standardized, low-technology physical fitness test. METHODOLOGY/PRINCIPAL FINDINGS: Four villages in coastal Kenya were surveyed during 2009-2010. Children 5-18 years were tested for infection with Schistosoma haematobium (Sh), malaria, filaria, and geohelminth infections by standard methods. After anthropometric and hemoglobin testing, fitness was assessed with the 20 mSRT. The 20 mSRT proved easy to perform, requiring only minimal staff training. Parasitology revealed high prevalence of single and multiple parasitic infections in all villages, with Sh being the most common (25-62%). Anemia prevalence was 45-58%. Using multiply-adjusted linear modeling that accounted for household clustering, decreased aerobic capacity was significantly associated with anemia, stunting, and wasting, with some gender differences. CONCLUSIONS/SIGNIFICANCE: The 20 mSRT, which has excellent correlation with VO(2), is a highly feasible fitness test for low-resource settings. Our results indicate impaired fitness is common in areas endemic for parasites, where, at least in part, low fitness scores are likely to result from anemia and stunting associated with chronic infection. The 20 mSRT should be used as a common metric to quantify physical fitness and compare sub-clinical disability across many different disorders and community settings

Effect of exercise training on liver function in adults who are overweight or exhibit fatty liver disease: a systematic review and meta-analysis

ObjectiveExercise training has been shown to have beneficial effects on liver function in adults overweight or with fatty liver disease. To establish which exercise programme characteristics were likely to elicit optimal improvements.DesignSystematic review and meta-analysis of randomised, controlled trials.Data sourcesPubMed, CINAHL and Cochrane controlled trials registry searched (1966 to 2 October 2015).Eligibility criteria for selecting studiesExercise intervention, with or without dietary intervention, versus usual care in adults undertaking, exercise training, who were overweight, obese or exhibited fatty liver disease (non-alcoholic fatty liver disease or non-alcoholic steatohepatitis).ResultsWe included 21 randomised controlled trials, totalling 1530 participants. Exercise intervention studies with total exercise programme workload &gt;10 000 kcal produced significant improvements in intrahepatic fat, −3.46% (95% CI −5.20% to −1.73%), p&lt;0.0001, I2=73%; effect size (standardised mean difference, SMD) −1.77 (−3.11 to −0.42), p=0.01, I2=77%. When data from only exercise studies were pooled, there was a reduction in fasting free fatty acids (FFAs) −74.15 µmol/L (95% CI −118.47 to −29.84), p=0.001, I2=67% with a large effect size (SMD) −0.94 (−1.36 to −0.52), p&lt;0.0001, I2=0%. When data from only exercise studies were pooled, there was a significant reduction in insulin MD −1.88 UL (95% CI −3.43 to −0.34), p=0.02, I2=31%. The liver enzymes, alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transpeptidase, were not significantly altered with exercise.ConclusionsExercise training reduces intrahepatic fat and FFAs while increasing cardiorespiratory fitness. An aggregate exercise programme energy expenditure (&gt;10 000 kcal) may be required to promote reductions in intrahepatic fat.</jats:sec

Cervical nodal volume for prognostication and risk stratification of patients with nasopharyngeal carcinoma, and implications on the TNM-staging system

published_or_final_versio

Friction and wear behavior of glasses and ceramics

Adhesion, friction, and wear behavior of glasses and ionic solids are reviewed. These materials are shown to behave in a manner similar to other solids with respect to adhesion. Their friction characteristics are shown to be sensitive to environmental constituents and surface films. This sensitivity can be related to a reduction in adhesive bonding and the changes in surficial mechanical behavior associated with Rehbinder and Joffe effects. Both friction and wear properties of ionic crystalline solids are highly anisotropic. With metals in contact with ionic solids the fracture strength of the ionic solid and the shear strength in the metal and those properties that determine these will dictate which of the materials undergoes adhesive wear. The chemical activity of the metal plays an important role in the nature and strength of the adhesive interfacial bond that develops between the metal and a glass or ionic solid

Design and rationale of a multi-center, pragmatic, open-label randomized trial of antimicrobial therapy - the study of clinical efficacy of antimicrobial therapy strategy using pragmatic design in Idiopathic Pulmonary Fibrosis (CleanUP-IPF) clinical trial

Compelling data have linked disease progression in patients with idiopathic pulmonary fibrosis (IPF) with lung dysbiosis and the resulting dysregulated local and systemic immune response. Moreover, prior therapeutic trials have suggested improved outcomes in these patients treated with either sulfamethoxazole/ trimethoprim or doxycycline. These trials have been limited by methodological concerns. This trial addresses the primary hypothesis that long-term treatment with antimicrobial therapy increases the time-to-event endpoint of respiratory hospitalization or all-cause mortality compared to usual care treatment in patients with IPF. We invoke numerous innovative features to achieve this goal, including: 1) utilizing a pragmatic randomized trial design; 2) collecting targeted biological samples to allow future exploration of 'personalized' therapy; and 3) developing a strong partnership between the NHLBI, a broad range of investigators, industry, and philanthropic organizations. The trial will randomize approximately 500 individuals in a 1:1 ratio to either antimicrobial therapy or usual care. The site principal investigator will declare their preferred initial antimicrobial treatment strategy (trimethoprim 160 mg/ sulfamethoxazole 800 mg twice a day plus folic acid 5 mg daily or doxycycline 100 mg once daily if body weight is < 50 kg or 100 mg twice daily if ≥50 kg) for the participant prior to randomization. Participants randomized to antimicrobial therapy will receive a voucher to help cover the additional prescription drug costs. Additionally, those participants will have 4-5 scheduled blood draws over the initial 24 months of therapy for safety monitoring. Blood sampling for DNA sequencing and genome wide transcriptomics will be collected before therapy. Blood sampling for transcriptomics and oral and fecal swabs for determination of the microbiome communities will be collected before and after study completion. As a pragmatic study, participants in both treatment arms will have limited in-person visits with the enrolling clinical center. Visits are limited to assessments of lung function and other clinical parameters at time points prior to randomization and at months 12, 24, and 36. All participants will be followed until the study completion for the assessment of clinical endpoints related to hospitalization and mortality events. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02759120

General model for water monomer adsorption on close-packed transition and noble metal surfaces

Ab initio density functional theory has been used to investigate the adsorption of H2O on several close-packed transition and noble metal surfaces. A remarkably common binding mechanism has been identified. On every surface H2O binds preferentially at an atop adsorption site with the molecular dipole plane nearly parallel to the surface. This binding mode favors interaction of the H2O 1b(1) delocalized molecular orbital with surface wave functions

Risk of bias and the reporting of surgeons' experience in randomized controlled trials of total hip and total knee arthroplasty: A systematic review

Rationale, aims, and objectives: The potential bias introduced by surgeons' lack of comparable, relevant experience when performing the procedures in different arms of randomized controlled trials (RCTs) is arguably not well-managed or reported. The aim of this work was to review the frequency and nature with which surgeons' relevant experience is reported in RCTs of total hip (THA) and total knee arthroplasty (TKA), and to relate this to other risk of bias domains for this study design. Methods: A systematic review of RCTs comparing different minimally invasive procedures for TKA and comparisons of THA and hemiarthroplasty (HA). We searched MEDLINE, EMBASE, Science Citation Index, The Cochrane Library, Conference Proceedings Citation Index-Science (CPCI-S), Current Controlled Trials, and Clinical Trials.gov. Results: Seventy-five relevant RCTs were identified, 65 RCTs comparing minimally invasive with standard or other minimally invasive approaches to TKA, and 10 for THA compared with HA. Risk of bias based on the reported details of surgeons' relevant experience was categorized as low, high, or unclear. There was a clear distinction before and after 2009, with a substantial decrease in trials at high or unclear risk of bias after this date. There were no strong associations between this domain and other, standard risk of bias domains for RCTs. Conclusion: The surgeons' relevant experience in an evaluated procedure is often poorly reported but has improved since 2009. The variable is not adequately captured by any other risk of bias domain. Future work should concentrate on conducting research on a much larger sample of studies and in procedures other than knee and hip arthroplasty

Need for Alloparental Care and Attitudes Toward Homosexuals in 58 Countries: Implications for the Kin Selection Hypothesis

Homosexuality is an evolutionary puzzle. Many theories attempt to explain how a trait undermining individual reproduction can be maintained, but experimental testing of their predictions remains scarce. The kin selection hypothesis (KSH) is an important theoretical framework to account for the evolution of human homosexuality, postulating that its direct cost to reproduction can be offset by inclusive fitness gains through alloparental assistance to kin. Consistent evidence in support of the KSH has only been garnered from research on Samoan fa’afafine (i.e. feminine, same-sex attracted males), whereas research in numerous industrialized societies has repeatedly failed to secure empirical support for the theory. Here, we propose an alternative test of the KSH by investigating how need for alloparental care influences women’s attitudes toward homosexuality (AtH). AtH would influence the likelihood of women receiving alloparental care from homosexual kin. We applied logistic regression analysis to a large dataset (17,295 women in 58 countries) derived from the World Values Survey. As predicted by the KSH, women who are potentially most in need of alloparental support exhibit significantly more positive attitudes toward homosexuals. For single mothers who expressed parental care concerns, each additional child mothered was associated with an increase of 1.24 in their odds of exhibiting positive attitudes toward homosexuals. Our study is the first to provide circumstantial evidence in support of the KSH on a global scale